a man or boy

a fine old fellow; a nice little fellow.

Informal . beau; suitor

Mary had her fellow over to meet her folks.

Informal . person; one

They don't treat a fellow very well here.

a person of small worth or no esteem.

a companion; comrade; associate

They have been fellows since childhood.

a person belonging to the same rank or class; equal; peer

The doctor conferred with his fellows.

one of a pair; mate; match

a shoe without its fellow.

Education .

a graduate student of a university or college to whom an allowance is granted for special study.

British . an incorporated member of a college, entitled to certain privileges.

a member of the corporation or board of trustees of certain universities or colleges.

a member of any of certain learned societies

a fellow of the British Academy.

Obsolete . a partner.

to make or represent as equal with another.

Archaic . to produce a fellow to; match.

belonging to the same class or group; united by the same occupation, interests, etc.; being in the same condition

fellow students; fellow sufferers.

noun

enemy

noun

assistant , associate , cohort , companion , compeer , comrade , concomitant , confrere , consort , coordinate , counterpart * , coworker , double , duplicate , equal , instructor , lecturer , match , mate , member , partner , peer , professor , reciprocal , twin , chap* , beau , affiliate , ally , colleague , confederate , copartner , chum , crony , coequal , equivalent , counterpart , adjutant , bloke , bon ami , boy , brother , buster , cadet , chap , coadjutor , coeval , collaborator , compatriot , friend , gent , gentleman , guy , hombre , lad , mac , man , person , worker